Stair Stringer Attachment

How you attach the stair stringers to the top of the deck and to any landings will be critical. You should reinforce the rim behind the stairs to provide a solid base for attachment. Use positive connections to install stair stringers using stair stringer connectors to the front face of the rim to provide adequate support.

If your first tread steps down from the deck, you must extend the rim joist to create a solid surface below the deck rim to attach it to. You should attach 2x6 or 2x8 support framing under the rim flush to the bottom of the stringer.

The stairs will hang here.

Install a piece of blocking below the rim joist to extend the attachment surface for your stairs stringers.

Use a level to mark the top step.

Measure down from the top of the deck and mark the top of your stair stringers with a level. For example, if each stair will be 6 3/8" finished height, we will measure down 7 3/8" to compensate for the missing stair tread.

Mark the locations for the stringers.

Mark the location for each stair stringer. Most wood stairs use 16" on center. Follow the manufacturer's guidelines for composite decking. Most composite decking materials require 12" or even 10" on center spacing.

A positive stringer connection.

Bend your stair stringer connectors to the correct angle. Hold the connector under the stringer and raise the stringer to the proper height. Then, mark the height of the connector. Repeat for each stringer attachment. Use 10d - 1.5" hot-dipped galvanized nails.

Make sure the top of the stringers are level.

Nail the stair stringer connectors into place. Then, nail the 2x12 stair stringers to the connector side flange and bottom.